Featured Research

from universities, journals, and other organizations

Scientists identify possible key to drug resistance in Crohn's disease

Date:
January 8, 2014
Source:
Scripps Research Institute
Summary:
Scientists have identified a normally small subset of immune cells that may play a major role in the development of Crohn's disease generally and in disease-associated steroid resistance specifically.

Two-thirds to three-quarters of the estimated 700,000 Americans living with Crohn's disease, an autoimmune condition that can disrupt the entire gastrointestinal tract, will require surgery at some point during their life. Patients and physicians often turn to this surgical intervention after a patient develops resistance to current treatments, such as steroids.

Now scientists from the Florida campus of The Scripps Research Institute (TSRI) have identified a normally small subset of immune cells that may play a major role in the development of Crohn's disease generally and in disease-associated steroid resistance specifically.

The study, published this week in an advance, online edition of the Journal of Experimental Medicine, focused on Th17 cells, part of a family of white blood cells that have been implicated in numerous autoimmune diseases, including Crohn's disease.

In the new study, the researchers found that a subset of TH17 cells in humans expresses the multidrug transporter MDR1 and that these cells are linked to inflammation in Crohn's patients. MDR1 -- a protein famous for promoting drug-resistance in tumors -- may also act as a survival and steroid resistance factor in T cells, particularly in harsh environments such as the inflamed gut mucosa of Crohn's disease patients.

"Our study is the first to identify and characterize this uniquely pro-inflammatory T-cell subset," said biologist Mark Sundrud, a TSRI assistant professor who led the study. "We were able to sort these cells directly out of damaged tissue resected from Crohn's patients and found that these pro-inflammatory cells are over-expressing genes that contribute to disease."

Within healthy individuals, only approximately 5 to 10 percent of CD4+ T cells are MDR1-expressing TH17 cells. In contrast, the study found that of the CD4+ T cells found in actively inflamed tissue taken from Crohn's patients, nearly 60 percent were MDR1+ TH17 cells.

The study also showed that these cells are resistant to both natural and synthetic steroids, a class of drugs considered a first-line defense against most autoimmune diseases.

"If a T cell expresses MDR1, it is likely to have an unfair growth advantage over surrounding T cells," Sundrud said. "When exposed to steroids, it's this subset of cells that will survive and thrive."

Although it is unclear whether these pro-inflammatory cells become more prominent in patients over time, these findings suggest that steroid treatment itself may be directly responsible for the accumulation of these cells in Crohn's patients. Sundrud and his colleagues continue to investigate.


Story Source:

The above story is based on materials provided by Scripps Research Institute. Note: Materials may be edited for content and length.


Journal Reference:

  1. Radha Ramesh et al. Pro-inflammatory human Th17 cells selectively express P-glycoprotein and are refractory to glucocorticoids. J Exp Med, January 2014 DOI: 10.1084/jem.20130301

Cite This Page:

Scripps Research Institute. "Scientists identify possible key to drug resistance in Crohn's disease." ScienceDaily. ScienceDaily, 8 January 2014. <www.sciencedaily.com/releases/2014/01/140108123744.htm>.
Scripps Research Institute. (2014, January 8). Scientists identify possible key to drug resistance in Crohn's disease. ScienceDaily. Retrieved October 20, 2014 from www.sciencedaily.com/releases/2014/01/140108123744.htm
Scripps Research Institute. "Scientists identify possible key to drug resistance in Crohn's disease." ScienceDaily. www.sciencedaily.com/releases/2014/01/140108123744.htm (accessed October 20, 2014).

Share This



More Health & Medicine News

Monday, October 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

How Nigeria Beat Its Ebola Outbreak

How Nigeria Beat Its Ebola Outbreak

Newsy (Oct. 20, 2014) The World Health Organization has declared Nigeria free of Ebola. Health experts credit a bit of luck and the government's initial response. Video provided by Newsy
Powered by NewsLook.com
Another Study Suggests Viagra Is Good For The Heart

Another Study Suggests Viagra Is Good For The Heart

Newsy (Oct. 20, 2014) An ingredient in erectile-dysfunction medications such as Viagra could improve heart function. Perhaps not surprising, given Viagra's history. Video provided by Newsy
Powered by NewsLook.com
Ebola Worries End for Dozens on U.S. Watch Lists

Ebola Worries End for Dozens on U.S. Watch Lists

Reuters - US Online Video (Oct. 20, 2014) Forty-three people who had contact with Thomas Eric Duncan, the first person diagnosed with Ebola in the U.S., were cleared overnight of twice-daily monitoring after 21 days of showing no symptoms. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
Fauci: Ebola Protocols to Focus on Training

Fauci: Ebola Protocols to Focus on Training

AP (Oct. 20, 2014) Dr. Anthony Fauci, head of the National Institute of Allergy and Infectious Diseases, says he expects revised CDC protocols on Ebola to focus on training, observation and ensuring health care workers are more protected. (Oct. 20) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins